Catheter placement unit for paracervical anesthesia



J. R. REIF ET AL CATHETER PLACEMENT UNIT FOR PARACERVICAL ANEST HESIA 2 Sheets-Shem; 1

April 28, 1970 Filed Nov. 16, 1967 INVE N TORS JAMES RQREIF PERRY E. PRATHER A ril 28, 1970 CATHETER PLACEMENT UNIT FOR PARACERVICAL ANESTHESIA Filed Nov. 16, 1967 J. R. REIF L 2 Sheets-$heet 2 IN VE N TORS JAMES R. REIF PERRY E. PRATHER wwaw ATTORNEY United States Patent 3,508,545 CATHETER PLACEMENT UNIT FOR PARACERVICAL ANESTHESIA James R. Reif, Midland, and Perry E. Prather, Saginaw Township, Saginaw County, Mich., assignors to Dow Cormng Corporation, Midland, Mich., a corporation of Michigan Filed Nov. 16, 1967, Ser. No. 683,679 Int. Cl. A61m 5/00 U.S. Cl. l28215 5 Claims ABSTRACT OF THE DISCLOSURE An improved catheter and means of placement thereof is disclosed. The catheter consists of a flexible tube having a resilient barb-shaped protuberance adjacent to one end which is adapted to releasably secure the catheter in place when in use. The catheter placement unit consists of the catheter, a tubular guide, and an introducer needle having a slotted trocar at one end. The use of the catheter placement unit in a continuous paracervical anesthesia administration system is also disclosed.

BACKGROUND OF THE INVENTION The present invention relates to the field of surgical devices in general and, more particularly, to catheters for injecting or infusing fluids into patients.

There is frequently a necessity to administer parenteral solutions continuously or intermittently to patients over a relatively long period of time. In such cases, the common practice has been either to puncture the patients flesh or vein with a metal hypodermic needle and leave the needle in place over the required period or to cut surgically into the flesh or vein with a scapel, insert a flexible plastic tube, and suture the opening to hold the tube in place over the required period. Both of these practices present difficulties. For example, when a metal hypodermic needle is left in the patient over an extended period of time, the patient must be immobilized to prevent the point of the in-dwelling needle from accidentally damaging the surrounding tissue. Should such an accident ever happen, another puncturing of the flesh or vein of the patient and a reinsertion of the needle would be required, resulting in additional pain and discomfort to the patient. Further, continued immobilization of the parts of the patients body might cause the patient severe discomfort by reason of the part being immobilized for a long period of time.

More recently, a new technique has been developed which involves puncturing the flash or vein of a patient with a sterile hollow needle and then threading a sterile, flexible plastic catheter into the flesh or vein. The needle is then removed and the catheter allowed to remain in place as long as desired. However, this new technique has also presented difliculties'.

Frequently, the catheter is found diflicult to properly guide into the patients flesh or vein. In some instances the catheter is guided through the hollow needle with a stylet, which creates the possibility of perforating the vein wall when the catheter is advanced. Other catheters have curls or hooks at their inserted ends which also require the insertion and removal to be carried out with a stylet, and these catheters frequently cause damage to the mucosa of the patient when they re-curl after the stylets are removed. Such catheters must be inserted relatively deep into the patients flesh in order to adequately secure them. In addition, some heretofore known devices use split or slotted needles, which create a danger of an accumulation of an intraluminal plug of tissue upon insertion of the needle, interfering with the ultimate advancement of the catheter through the needle.

SUMMARY OF THE INVENTION The primary object of the present invention, therefore, is to provide an improved catheter and catheter placement unit which will be free from the aforementioned and other disadvantages of prior devices of this type.

More particularly, it is an object of the present invention to provide a catheter placement unit which allows administration to a patient of parenteral solutions, continuously or intermittently, over a relatively long period of time with a minimumv of discomfort to the patient, and which is easily inserted, as well as inexpensively manufactured.

Another object of the present invention is to provide a means for administering fluids into a patient which eliminates the necessity of immobilizing the patients body after the device has been inserted in the patient and enables the easy insertion of a flexible administering device into the punctured flesh or vein of the patient without the use of a stylet.

Still another object of the present invention is to provide a continuous paracervical anesthesia administration device which is easily inserted and safe for the mother and infant, as well as free from the aforementioned disadvantages of prior devices.

In accordance with these and other objects, there is provided by the present invention, a catheter placement unit preferably made of silicone rubber and consisting of a tubular guide, an introducer needle having at one end a slotted trocar for puncturing the flesh or vein of a patient, and a catheter which has a flexible tube having adjacent one end a resilient barb-shaped protuberance. The guide provides a means for accurately placing the catheter, while the introducer needle punctures the patients flesh or vein and also carries the catheter to the injection site. The resilient barb-shaped protuberance fits through the slot in the trocar and provides a means for holding the catheter in place after the guide and introducer needle are withdrawn. The resilient barbshaped protuberance further provides a means by which the catheter may be carried to the injection site by the introducer needle, thereby eliminating the need for threading it in with a stylet. Because the catheter is made of flexible silicon rubber, the patient need not be immobilized after its insertion, as there is no danger of accidental puncture from such a flexible catheter. Further, the possibility of damage and danger to the patient is minimized.

BRIEF DESCRIPTION OF THE DRAWING Other objects and many more attendant advantages will become obvious to those skilled in the art by reading the following detailed description in connection with the accompanying drawings wherein:

FIG. 1 is a view in elevation showing the tubular guide of the present invention pressed against a cross-section of any fleshy surface;

FIG. 2 is a View in elevation showing the introducer needle of the present invention;

FIG. 3 is a side view in elevation showing the catheter of the present invention inserted in a cross-section of any fleshy surface;

FIG. 4 is a side view in elevation showing the catheter placement unit of the present invention inserted in a cross-section of any fleshy surface;

FIG. 5 is a cross-sectional view of a variation of the catheter placement unit of the present invention showing the tubular guide pressed against a cross-section of any fleshy surface;

FIG. 6 is a view in elevation of the embodiment of FIG. 5 with the needle inserted in a cross-section of any fleshy surface; and

FIG. 7 is a view in elevation of the embodiments of FIGS. and 6 showing the catheter embedded in the flesh and the tubular guide and needle withdrawn.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings wherein like reference numerals designate like or corresponding parts throughout the figures thereof, there is shown in FIG. 4, a catheter placement unit, shown generally as 10. While it is to be understood that the catheter placement unit 10 can be used generally as any other catheter can be used, one use for which the catheter placement unit of the present invention is particularly suited is in a continuous use of long and sharp hypodermic needles in the This is true because of the near impossibility of immobilization of the pertinent areas of a mothers body during childbirth and because of the obvious danger to the mother and child inherent in the insertion and continuous use of long and sharp hypodermic needles in the cervix of the mother during childbirth.

In a continuous paracervical anesthesia administration system, two catheters are inserted; preferably one at the 2-4 oclock position and one at the 8-10 oclock position in the patients lateral fornix. The tubular guide 11, shown in FIG. 1 and made of some suitable plastic or rubber material, is placed against the vaginal mucosa in the patients lateral fornix at either of the desired positions, as is illustrated by the fleshy surface 12 in FIG. 1.

The introducer needle, shown generally as 13 in FIG. 2, has already had the catheter, shown generally as 14 in FIG. 3, threaded through it prior to the beginning of the anesthesia administration. The needle 13 consists of a tube 15 having an outwardly extending radial enlargement 16 at one end and a trocar 18 which is slotted as can be seen at 20 in FIG. 2. The tube 15 is also made of some suitable plastic or rubber material, and the slotted trocar is preferably made of stainless steel.

The catheter 14, which is prethreaded into the needle 13, consists of a flexible silicone rubber tube 22 which has a resilient barb-shaped silicone rubber protuberance 24 adjacent one end. The catheter 14 and the protuberance 24 are preferably made of silicone rubber because of its inertness to the human body and its softness and pliability, which allows the catheter 14 and protuberance 24 to pass through the vaginal mucosa, or any other fleshy surface, without causing trauma.

When the catheter 14 is fully threaded through the needle 13, the resilient protuberance 2'4 fits through the slot 20 in the trocar 18, as may best be seen in FIG. 4. Thus, as shown in FIG. 4, when the needle 13 is passed through the guide 11 until the radial enlargement 16 contacts the upper end of the guide 26, the catheter 14 is carried to the injection site in the vaginal mucosa by the trocar 18 pushing against the protuberance 24. Obviously, the radial enlargement 16 serves to stop the needle 13 at a predetermined desired puncture depth, generally about 1 centimeter. Thus, the catheter of the present invention may be used to make desirable superficial injections. Such superficial injections cannot be made by catheters having a hook or curve at their inserted ends, since they must be inserted relatively deep in the patients flesh in order to adequately secure them.

When the guide 11 and needle 13 are then withdrawn, the catheter 14 remains in the vaginal mucosa shown as 12 in FIG. 3. A catheter adapter is then inserted into the end of the catheter outside the patients body. If a bloody tap is encountered, the catheter is withdrawn and reinserted before the adapter is inserted. The catheter 13 is then ready for use and may simply be taped to the mothers abdomen for continuous or intermittent injections of an anesthetic fluid while the patient is in the labor room.

Finally, the catheter is either dislodged with the delivery of the child or by a mild pull or traction on the catheter after the delivery of the child. Thus, no reinstrumentation is required to remove the catheter from the patient.

The resilient barb-shaped protuberance 24 clearly has two functions. Firstly, the protuberance provides a means by which the catheter 14 may be carried to the injection site by the introducer needle 13. Thus, the dangers and difficulties prior art devices presented by requiring the forcing of a catheter, usually with a stylet, through the introducer needle are eliminated. Further, the possibility of the slotted needle accumulating an intraluminal plug of tissue which would interfere with the insertion of a catheter through the needle is obviated by the presence of the protuberance 24 in the slot of the trocar 18 upon its insertion.

Secondly, the protuberance functions as a means for holding the catheter in the patient once it has been inserted, thereby preventing accidental displacement of the catheter. A silicone rubber is preferred for the catheter and protuberance because it is flexible, sterilizable, and inert to the human body. Further, the silicone rubber protuberance presents a resilient material upon which the flesh can take hold and releasably secure the catheter in place. Other materials, such as Teflon or polyethylene, which are relatively more rigid, tend to slip back out of the flesh easily, or if they do stay in place, tend to be difficult to remove once they are no longer needed. The protuberance of the present invention releasably secures the catheter in place without need of being deeply inserted into the flesh and without scratching or damaging the mucosa of the patient.

Thus, due to the flexibility of the catheter tube and the protuberance, the immobilization of the patient required by prior art devices is eliminated. In fact, when the catheter of the present invention is used in a paracervical anesthesia system, the expectant mother i completely ambulatory between the time the catheters are inserted and the actual delivery of the child begins.

In one specific embodiment of the present invention, the tubular guide was made of polypropylene, was 8 /2 inches long, with an outer diameter of 0.218 inch and an inner diameter of 0.172 inch. The introducer needle was 11.075 inches long. The slotted trocar was made of stainless steel and the tube was made of polypropylene. The length of the radial enlargement was 2 inches and its outer diameter was 0.218 inch. The length of the tube, including the radial enlargement, was 10 /2 inches. The inner diameter of the tube was 0.065 inch and the outer diameter of the tube was 0.146 inch. The trocar was a 17 gauge needle and was 0.575 inch long. The slot had a width of 0.038 inch and a height of 0.218 inch. The catheter tube was 16 inches long and the barb-shaped protuberance had a width of 0.266 inch, a depth of 0.035 inch and a height of 0.105 inch. Both the catheter tube and protuberance were made from silicone rubber.

There is hown in FIG. 5 a variation of the catheter placement unit of the present invention, shown generally as 30. The catheter 14 shown in FIG. 3 is also used in this variation. The introducer needle 13 shown in FIG. 2 has been modified, so that the outwardly extending radial enlargement 16 forms a knob or handle 16', as can be seen in FIG. 5. The tubular guide 11 shown in FIG. 1 has also been modified to include an outwardly extending radial enlargement 31 at one end. This enlargement has within it a groove or slot 32 into which a spring 34 may fit and rest upon its lower lip. The enlargement also has within it another groove 36 into which at least a portion of the introducer needle handle 16' may be freely inserted.

The introducer needle is permanently inserted into the tubular guide at the time of manufacture in this variation. Thus, the lower edge of the introducer needle handle 16 can freely move axially in the groove 36, but its axial movement is stopped by both the upper and lower lips of that groove. The spring 34 rest on the lower lip of the groove 32 and biases the lower edge of the introducer needle handle 16' against the upper lip of the groove 36, when there is no axial force being exerted inwardly on the handle. When the introducer needle is in this position, the slotted trocar 18 is wholly within the tubular guide, as can be seen in FIG. 5. Obviously, when the catheter 14 is threaded into the introducer needle, the barb-shaped protuberance 24 is also wholly within the tubular guide 11. The catheter may be threaded at the time of manufacture of the catheter placement unit or just prior to its use.

When an inward axial force is exerted on the introducer needle handle 16', by pressure from a doctors thumb, for example, the lower edge of that handle can move freely to the lower lip of the groove 36, which acts as a limit stop. The spring 34 is compressed within the groove 32. Consequently, the slotted trocar 18 and the catheter tube and protuberance 24 are forced outside of the tubular guide 11 a distance equal to the width of the groove 36.

Once the inward axial force is removed from the introducer needle handle 16, the spring 34 returns to its original hape and forces the lower edge of the handle 16 against the upper lip of the groove 36. Consequently, the slotted trocar 18 is also wholly drawn into the tubular guide 11. If the trocar 18 has been inserted into a fleshy surface, such as 12 in FIG. 6, the barb-shaped protuberance 24 will remain in that surface and will not be drawn back into the tubular guide 11 along with the trocar.

To facilitate handling of the catheter placement unit 30, a finger guide 38 has also been attached to the tubular guide 11. This finger guide may be molded as a flange on the tubular guide or may be merely aflixed to it by a suitable adhesive. Also, a radial slot 37 is provided in the introducer needle handle 16. The catheter tube 22 can be threaded through the slot 37, thereby avoiding the possibility of pulling the catheter from the flesh into which it has been inserted by inadvertently pinching the tube 22 against the top of the handle 16' while the spring 34 is returning the handle 16 to its original position. If desired, a substantially radial bore may be substituted for the slot 37.

The catheter placement unit 30 can be used in a continuous paracervical anesthesia administration system. The tubular guide 11 is placed against the vaginal mucosa of the patient as shown by 12 in FIG. 5. The doctor then merely pushes the introducer needle handle 16' into the guide tube, as shown in FIG. 6. Consequently, the slotted trocar 18 is inserted into the patients vaginal mucosa and carries the catheter and barb-shaped protuberance 24 along with it. The doctor then merely releases the handle 16' and the slotted trocar 18 springs back into the tubular guide, while the catheter is held in the mucosa by the barb-shaped protuberance 24.

This variation of the present invention allows the doctor to insert the catheter into the patient with just one hand. Further, since the introducer needle springs back into the tubular guide once the handle is released, there is no danger of scratching the mucosa of the patient while the needle is being withdrawn from the vagina.

The catheter placement unit of the present invention can be used in many applications, and the description of its use in a continuous paracervical anesthesia administration system is merely exemplary and not intended to limit the scope of the present invention.

Many modifications and variations of the abovedescribed embodiment of the invention will be obvious to those skilled in the art. Accordingly, within the scope of the appended claims, the invention may be practiced otherwise than a specifically described.

That which is claimed is:

1. A catheter placement unit comprising in combination:

an introducer needle consisting of a tube having at one end an outwardly extending radial enlargement and at the other end a slotted trocar for puncturing a fleshy surface, and

a flexible catheter having adjacent to one end a resil ient barb-shaped protuberance for releasably securing said catheter in said fleshy surface, said catheter threaded through said introducer needle in a manner such that said protuberance fits through the slot in said slotted trocar and provides the means by which said catheter is carried into said fleshy surface by said slotted trocar when said fleshy surface is punctured thereby.

2. A catheter placement unit comprising in combination:

a tubular guide for accurately placing said catheter placement unit and having at least one end adapted to press snugly against a fleshy surface,

an introducer needle inserted in said tubular guide, said needle consisting of a tube having at one end an outwardly extending radial enlargement for limiting the insertion of said introducer needle into said tubular guide to a predetermined length and having at the other end a slotted trocar for puncturing said fleshy surface when said introducer needle is inserted in said tubular guide to said predetermined length, and

a flexible catheter having adjacent to one end a resilient barb-shaped protuberance for releasably securing said catheter in said fleshy surface, said catheter threaded through said introducer needle in a manner such that said protuberance fits through the slot in said slotted trocar and provides the means by which said catheter is carried into said fleshy surface by said slotted trocar when said introducer needle is inserted in said tubular guide to said predetermined length.

3. A catheter placement unit as described in claim 2,

wherein said catheter is made of silicone rubber.

4. A catheter placement unit as described in claim 2,

wherein:

at least a portion of said introducer needle is permanently inserted within said tubular guide,

said radial enlargement on said introducer needle forms a handle, and

said tubular guide has an outwardly extending radial enlargement having a groove therein for receiving and retaining at least a portion of said introducer needle handle;

and further comprising a spring seated in said tubular guide enlargement and adapted to hold said intro ducer needle trocar wholly within said tubular guide until an axial force is placed upon said introducer needle handle, thereby compressing said spring and forcing said trocar outside of said tubular guide, and further adapted to bias said introducer needle trocar to a position Wholly within said tubular guide when the force on said introducer handle is released.

5. A catheter placement unit as described in claim 4,

wherein said introducer needle handle has a radial slot adapted to allow said catheter to pass therethrough.

References Cited UNITED STATES PATENTS 1,640,311 8/1927 Dawes 128-347 X 2,880,724 4/1959 Velarde 128--215 3,308,819 3/1967- Arp 128-215 3,359,978 12/1967 Smith 128-214.4 3,380,448 4/1968 Sadove et al 128-215 3,399,674 9/1968 Pannier et al. 128214.4

DALTON L. TRULUCK, Primary Examiner US. Cl. X.R. 128-2144, 347

UNITED STATES PATENT OFFICE @ERTIFICATE OF CORRECTION Patent No. 3,508,545 April 28 1970 James R. Reif et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 15, "tinuous use of long and sharp hypodermic needles in the" should read tinuous paracervical anesthesia administration system Signed and sealed this 22nd day of September 1970.

(SEAL) Edward M. Fletcher, Ir. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents 

